The Dana Farber Cancer Institute established the Molecular Biology Core Facilities to provide Institute laboratories convenient and cost-effective access to various molecular biology techniques and reagents such as oligonucleotides, synthetic, peptides, microprotein sequencing, mass analysis, DNA sequencing, genotyping, and protein-ligand analysis. As these services became established and usage increased the instrumentation has been continually upgraded, replaced and augmented by new instrumentation. This grant is requesting funds to purchase a BIAcore 3000 surface plasmon resonance to replace a pre1000 BIAcore instrument that has been supplying the analysis of biomolecular interactions as a service fore nine years. This instrument and service will be located within the Molecular Biology Core Facilities sharing space with the original instrument. A group of major users has been selected to represent all users of the service. Fifteen additional researchers at the institute are listed as intending on using the new instrumentation in the future. Because presently the service is supplied on an original BIAcore instrument the range of projects has become limited. The new instrument will allow greater sensitivity, greater dynamic range and the ability for all four cells to be used with the same analyte. The new instrument will allow the detection of molecules down to 200 daltons as well as the collection and recover of analytes. These recovered analytes can then be analyzed by mass analysis within the facility by both MALDI/TOF and nano-electrospray ion trap.